Regulation of Arbuscular Mycorrhizal Fungi in Citrus Root Hairs Mediated by Auxin Efflux Carrier Protein PtPINs

The study on trifoliate orange seedlings over 12 weeks found that arbuscular mycorrhizal fungi (AMF) initially inhibited root hair growth at 4, 6, and 8 weeks but promoted it at 10 and 12 weeks. This change was associated with increased levels of indole-3-acetic acid (IAA) and the modulation of auxin efflux carrier protein genes, especially PtPIN6, which may be crucial for root hair development. The research suggests that AMF enhances plant growth and root architecture by regulating auxin levels, indicating a complex interaction between AMF and auxins in citrus root development.